Heat Transfer, Combustion Commons^™

Carbon Fiber Recycler : Fiber Reclaimer, Alexander Edwards

All Undergraduate Projects

Boeing uses composite components for the 777x aircraft. The production of composite parts results in flashing (excess material) that must be trimmed and "thrown away" as scrap. Boeing is investigating means of recycling these scraps. The method proposed for this project is to delaminate and shred the composite material. The delamination process uses a ram to press two claw shaped devices together that bends and deforms the material in opposite directions. The chipper process uses counter rotating saw blades spaced 1/8” apart to produce small shredded material. This shredding material is pyrolyzed (heated) to decay the resin leaving the carbon …

Composite Recycler: Frame, Alfonso Olivera

All Undergraduate Projects

How can composites be recycled? The Composite Recycler is an ongoing project that started in September 2017. The purpose of this project was to create a machine that will delaminate the composites, cut them, and heat them up to separate the resin from the composites so they can be recycled. A group was put together for the 2018-2019 academic year to further the project as a whole improve the operation of the device. The existing base was used as well as the cutter and the power sources. The upgrades included; a housing to support the transport rollers and changing from …

Proposed Delivery And Return Water Temperatures For Dartmouth College Hot Water Network, Storm Mata

ENGS 86 Independent Projects (AB Students)

This study aimed to verify the viability of the planned hot water heating network at Dartmouth, and determine the necessary hot water radiator areas needed to satisfy the empirically-determined heat demand for buildings on campus, using 5 year of steam con- sumption data. In order to verify viability, the pressure and temperature of the delivery steam and return condensate of the current heating network were used to find the amount of heat delivered per pound of steam to campus. The above-mentioned steam consump- tion data were then used to find the max heat demand for the past five years and …

The Effects Of 3d Printing Parameters And Surface Treatments On Convective Heat Transfer Performance, Lucas N. Pereira

Electronic Theses and Dissertations

Additive manufacturing technology and applications have quickly expanded in many industries over the last five years. As additive manufacturing is studied and refined, improvements in resolution and strength have helped propel further growth of the industry. This study focuses on an additive manufacturing technology called fused filament fabrication (FFF). FFF involves the extrusion and layer-by-layer deposition of a molten thermoplastic material to create the desired part. One potential new application of fused filament fabrication is the manufacture of heat exchangers and heat sinks. This study focuses on developing baseline experimental data related to convective heat transfer coefficients over surfaces of …

Optimization And Comparison Of Over-Expanded And Other High Efficiency Four-Stroke Spark-Ignited Boosted Engines, Zhuyong Yang

Dissertations, Master's Theses and Master's Reports

Recent fuel economy and emission regulations are the major concern of the research and development of modern internal combustion engine. Such technologies include variable valve timing (VVT), direct injection (DI), turbocharging, downsizing, and over-expanded cycle are used by many manufacturers to improve engine fuel economy or increase power density.

Current Atkinson cycle technology in the production engine is mainly realized by an advanced valvetrain system to reduce the effective compression ratio while maintaining the same expansion ratio. Another approach to realize over-expanded cycle engine is to utilize a multi-link cranktrain mechanism. Although the Atkinson cycle was originally patented in the …

Fundamental Characteristics Of Supercritical Co2 Combustion, Raghu Veera Manikantachari Kancherla

Electronic Theses and Dissertations

The direct-fired supercritical CO2 (sCO2) cycle is conceptually superior to many of the trending energy production technologies due to their remarkably promising efficiency, environmental friendliness and cost. The accurate simulation of this combustion is very important because the operating conditions are very challenging to its experimentation. Hence, the current work focuses on identifying various thermal, transport, chemical kinetic models, investigating various fundamental characteristics and verifying the validity of important underlying modeling assumptions in focus to supercritical CO2 combustion. In the current work, various thermal and transport property models are identified based on accuracy, computational cost and ease of implementation for …

Modelling Of Aerodynamic Process For Coal Waste Dump Located In Geodynamically Dangerous Zone, Elena Vishnevskaya, Alexander Kobylkin, Valeriya Musina, Andrian Batugin, Vladimir Ponomarev, Oksana Vorobyeva

Publications

Previously made evaluations show confinement of fire coal waste dumps to geodynamically dangerous zones which in this work are considered as borders of active blocks of the earth crust. According to the hypothesis under development, when disposing the dumps in geodynamically dangerous zones (GDZ), which have a high penetrating, aerodynamic relation of the dumps with the environment occurs, making the dumps firing possible. Firing of the dumps inflicts environmental, social and material damage. This research is aimed to study possible mechanism of gas mass transfer through GDZ into the body of dump on the base of computer modeling of aerodynamic …

Simulations On Optimization Of Liquid Spray Burners & Operating Parameters, Pallavi Gajjar, Vinayak Malhotra

International Journal of Aviation, Aeronautics, and Aerospace

Spray burners form an essential part of any liquid propulsion system as they are responsible for injecting, atomizing, mixing and combusting the liquid fuel. Spray combustion used in aerospace applications like the liquid rocket engines, gas turbines or any other controlled environment for that matter places a huge emphasis on safe and effective operations. These applications make use of relatively small amounts of propellant volumes to generate enormous amounts of energy through combustion for producing thrust. For such cases involving enormous energy interactions, combustion comes with its own set of challenges. The predominant challenge among them all is that of …

Influence Of Micro-Nucleate Boiling On Annular Flow Regime Heat Transfer Coefficient Values And Flow Parameters – For High Heat-Flux Flow Boiling Of Water, Soroush Sepahyar

Dissertations, Master's Theses and Master's Reports

Analysis of results from steady and steady-in-the-mean high heat-flux (15 - 70 W/cm², with water as working fluid) shear driven annular flow-boiling experiments presented here - and low heat-flux (0.1- 1 W/cm², with FC-72 as working fluid) experiments presented elsewhere – together lead to a key conclusion. The conclusion is that heat carrying nucleation rates go often undetected by the typically used visualization approaches for flow boiling – as such flows often involve µm- to sub- µm scale bubble diameters in millimeter-scale ducts. These nucleation rates play a significant role in most of the so-called convective …

Multi-Scale, Capillary Assisted Copper Surfaces For Enhanced Pool Boiling Heat Transfer Processes, Chetan Agarwal

Dissertations, Master's Theses and Master's Reports

Phase-change heat transfer through pool boiling process offers a promising thermal management solution in applications wherein conventional air or single-phase liquid-based cooling methods prove inefficient such as for high-power electronics. Pool boiling process, which utilizes the latent heat of evaporation, provides a robust and efficient way to efficiently dissipate the excessive heat generated in a small footprint area in particular as seen in CPUs (Central Processing Units), GPUs (Graphics Processing Units), LEDs (Light Emitting Diodes), radars, and other demanding computing, sensing and surveillance electronics. Although boiling process has been studied for over five decades, it has not been yet adapted …

High Injection Pressure Dme Ignition And Combustion Processes: Experiment And Simulation, Xiucheng Zhu

Dissertations, Master's Theses and Master's Reports

With nearly smokeless combustion, Dimethyl Ether (DME) can be pressurized and used as a liquid fuel for compression-ignition (CI) combustion. However, due to its lower heating value and liquid density compared with diesel fuel, DME has a smaller energy content per unit volume. To obtain an equivalent energy content of diesel, approximately 1.86 times more quantity of DME is required. This can be addressed by a larger nozzle size or higher injection pressure. However, the effect of high injection pressure on DME spray combustion characteristics have not yet been well understood. In order to fill this gap, spray and combustion …

Study Of American Wood Pellet Stove Emissions, Sergio Gamarra

All Graduate Theses, Dissertations, and Other Capstone Projects

Problem: The EPA (Environmental Protection Agency) had not specified emissions performance standards for pellet burning stoves. Instead they were lumped in with cordwood burning stoves. IRETI’s decision to pursue this baseline study was guided by Minnesota’s concurrent “2025 Energy Action Plan” and the EPA’s pellet stove testing method development. Wood pellet fuel, a renewable resource, and the technology developed to utilize it for residential heating should be further studied to examine how together they both stand up to newly developed EPA emissions testing methods. This will establish a benchmark for testing American technology, thus guiding IRETI’s efforts of introducing foreign …

Solar Powered Atmospheric Water Generation, Ben Conser

Master’s Theses

Several atmospheric water generation (AWG) system configurations were analyzed to determine the feasibility of AWG as a method to combat water stress. In order to best combat water stress, AWG must be implemented in such a way which minimizes the energetic and monetary cost of water production. Thermodynamic and economic analyses were used to compare the performance of several AWG system configurations. Metrics such as specific energy consumption (SEC) and levelized cost of water (LCOW), which measure the energetic and monetary cost of water production respectively, were used to compare each system. Using this approach, the optimal system configuration was …

Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan

Williams Honors College, Honors Research Projects

In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …

Laser Ablation Of Aluminum, Erika Nosal, Zachary Rahe, Arthur Pamboukis

Williams Honors College, Honors Research Projects

The laser ablation of metal carries relevance in a variety of engineering industries. This includes, but is not limited to, processes such as micromachining, or implementation on aircraft weaponry. The latter application is the reasoning for why aluminum is the specific metal in consideration, as it is commonly used for the construction of aircraft components.

The scope of this project was to optimize the energy dispersed through laser ablation on aluminum by mathematical modeling. The transient conduction process in the aluminum was modeled using a 2-dimensional cylindrical coordinate system in both MATLAB and ANSYS/Fluent. These models were adopted to simulate …

Literature Survey Of Wet-Waste And Hydrothermal Carbonization System: A Comparative Evaluation, Ramat Olaide Yusuf

Dissertations and Theses

This thesis describes the process of Hydrothermal carbonization and a comparative assessment on recent work done on the process using different feedstocks such as Raw Apple (RA), Apple chip pomace (ACP), apple juice pomace (AJP), grape pomace (GP), macadamia nut-shell (MNS), Sewage Sludge (SS), Poultry Litter (PL) and Grape Marc (GM). The data obtained from the literature survey was compared with the data obtained by the CCL team on the SWPS gasifier (HTC of poultry litter) to obtain how carbon conversion efficiency, syngas composition, thermal efficiency, char production rate, gas production rate and energy utilization vary with carbonization process conditions, …

Investigation Of Heat Exchanger Effectiveness Using A Surface Coating Technology, Allen Duffy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diesel engine manufacturers continue to improve engine performance through increased thermal efficiency and reduced regulated emissions. The aftercooler located between the turbocharger air outlet and intake manifold experiences a wide range of operating conditions. Improving the heat transfer characteristics in the aftercooler can lead towards improved engine performance through increased charge air density. A surface coating has been proposed to enhance the heat transfer characteristics for a marine-based application on the water - side of the heat exchanger. To evaluate the efficacy of the coating, the rate of heat transfer with and without the coating was quantified in a controlled …

Computational Design Of Staged Pressurized Oxy-Coal Combustion, Gideon Ozioma Udochukwu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Staged pressurized oxy-coal combustion (SPOC) is nowadays a promising technology to be used for low-cost, low-emission, high-efficiency power generation. The objective of this thesis is to compliment the experiments ongoing at the Washington University, St. Louis (WUSTL) by means of numerical simulations, thereby providing better understanding of the fluid flow, turbulence, combustion characteristics, particle dynamics and heat transfer. Carbon dioxide (CO2) is injected alongside the coal, for its carriage. A small amount of methane (CH4) is also injected alongside the coal to maintain a steady flame. The simulations are performed for a 3D geometry with the following energy source distribution: …

Propagation And Morphology Of Premixed Flames In Obstructed Channels Under Atmospheric And Supercritical Conditions, Abdulafeez Akinola Adebiyi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The understanding of the morphology and propagation of premixed flames in channels is vital for the design and development of efficient propulsion systems requiring high heat release, such as pulse detonation engines, and for resolving accidental fire in industrial conduits. In this work, extensive computational simulation of premixed flames in channels (with rectangular and cylindrical cross sections) with closely packed obstacles are carried out with the goal of providing insights into flame propagation under various conditions which would be invaluable to the development and safety of energy and propulsion systems as well as for the mitigation of accidental fires in …

Scaling Analysis And Experimental Investigation Of A Rotating Detonation Engine, David Thomas Billups

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pressure gain combustion (PGC) technologies, specifically rotating detonation engines (RDEs), are poised to provide the next big leap in gas turbine engine advancement, significantly increasing the thermal. RDEs make use of thermodynamic advantages of isochoric as opposed to isobaric combustion. Theorized to increase thermal efficiency by up to 7% [1], the RDE would have significant impact on reducing anthropogenic carbon emissions. In addition to efficiency gains, the RDE also provides mechanical simplicity and reduced size advantages compared to it’s traditional counterparts and PGC competition.

The United States (U.S.) Department of Energy (DOE) National Energy Technology Laboratory (NETL) maintains and operates …

Experimental And Numerical Study Of The Stirling Engine Robust Foil Regenerator, Koji Yanaga

Graduate Theses, Dissertations, and Problem Reports (ETD)

The regenerator is located between the heat accepter and the heat rejecter of the Stirling engine. It works as a thermal energy storage component in the engine. Most of the regenerators are made of woven screen or random fiber. However, the flow going through the woven screen or random fiber is similar to the cylinders in crossflow which has flow separation. To achieve higher engine efficiency, it is required to design a regenerator which has higher convective heat transfer, lower pressure drops. Therefore, a parallel channel regenerator called a robust foil regenerator was designed and manufactured.

In this study, a …

Paddle Mixer-Extrusion Reactor For Torrefaction And Pyrolysis, Stas Zinchik

Dissertations, Master's Theses and Master's Reports

This work is focused on the fundamental understanding and the development of paddle mixer reactors (or modified screw augers). This work will contribute to the effort of the thermal conversion of biomass and wastes. We developed and studied two paddle systems (i) 25-mm lab-scale (up to 1 kg/hr) and (ii) 101-mm pilot-scale (up to 100 kg/hr). Thermal behavior of the two systems was studied and it was estimated that the lab-scale system has a high heating rate of up to 530 °C/s. Residence times were thoroughly measured and were determined as a function of rotation frequency and volume fraction. We …

Reduction Of Nox Emissions In A Single Cylinder Diesel Engine Using Sncr With In-Cylinder Injection Of Aqueous Urea, Anthony Timpanaro

UNF Graduate Theses and Dissertations

The subject of this study is the effect of in-cylinder selective non-catalytic reduction (SNCR) of NO_x emissions in diesel exhaust gas by means of direct injection of aqueous urea ((NH₂)₂CO) into the combustion chamber. A single cylinder diesel test engine was modified to accept an electronically controlled secondary common rail injection system to deliver the aqueous urea directly into the cylinder during engine operation.

Direct in-cylinder injection was chosen in order to ensure precise delivery of the reducing agent without the risk of any premature reactions taking place. Unlike direct in-cylinder injection of neat water, …

Modeling And Control Of Maximum Pressure Rise Rate In Rcci Engines, Aditya Basina

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) is a combustion strategy that burns fuel at lower temperatures and leaner mixtures in order to achieve high efficiency and near zero NOx emissions. Since the combustion happens at lower temperatures it inhibits the formation of NOx and soot emissions. One such strategy is Reactivity Controlled Compression Ignition (RCCI). One characteristic of RCCI combustion and LTC com- bustion in general is short burn durations which leads to high Pressure Rise Rates (PRR). This limits the operation of these engines to lower loads as at high loads, the Maximum Pressure Rise Rate (MPRR) hinders the use of …

Development Of A 2d Scr Catalyst On A Diesel Particulate Filter Model For Design And Control Applications To A Ultra Low Nox Aftertreatment System, Venkata Chundru

Dissertations, Master's Theses and Master's Reports

This research focuses on modeling and control of PM and NO_x in diesel engine exhaust using an SCR catalyst on a Diesel Particulate Filter (SCR-F). A 2D SCR-F model was developed that is capable of predicting internal states: 2D temperature, PM and NH₃storage distributions and filtration efficiency, pressure drop, PM mass retained in the PM cake and substrate wall and outlet NO, NO₂and NH₃concentrations. The SCR-F model was used to simulate a DOC + SCR-F + DOC + SCR ultra-low NOx system that can achieve > 99.5% NOx conversion efficiency.

The model was calibrated …

Networked Microgrid Optimization And Energy Management, Robert S. Jane

Dissertations, Master's Theses and Master's Reports

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of …